Generally, in reactive ion etching processes, an electric field plays a fundamental role. The chemistry in many discharges is affected strongly by the ion flux and energy distribution in the sheath and at the surface of walls and electrodes, which are in turn determined by the sheath electric field. Using measurements of electric fields in plasmas to provide a direct insight into the physics of discharges can be experimentally demanding. Moreover, the control of the electric field based on measurements is almost impossible to establish by feedback mechanisms. Therefore, the electric field in the sheath has to be controlled by external parameters, such as radiofrequency power and frequency combined with d.c. bias, radiofrequency circuit parameters, electrode dimensions and shape, pressure and composition of gas mixture. In order to control the electric field in the sheath with an external parameter, a link between one or more external parameters and a particular component of the electric field must be established.
Corrugated electrodes have been used in a number of applications in a variety of research areas, including such disparate fields as the development of biomedical and environmental chemistry devices or the development of capacitors, but were rarely applied to asymmetric discharges. In those rare cases where corrugated electrodes were applied to asymmetric discharges, the corrugated electrodes were applied in planar geometry with the aim to increase the average sheath thickness, reduce the electron and ion flux to the surface, and decrease the density of power dissipated into the electrode material. The driven electrode expansion concept is aimed to reduce the asymmetry of the dissipated power and the asymmetry in sheath voltage which is illustrated by the sheath voltage ratio relationship with the surface area ratio, as expressed in and decrease the density of power dissipated into the electrode material. The driven electrode expansion concept is aimed to reduce the asymmetry of the dissipated power and the asymmetry in sheath voltage which is illustrated by the sheath voltage ratio relationship with the surface area ratio, as expressed in
Equation (1)
                                          V            1                                V            2                          =                              (                                          A                2                                            A                1                                      )                    n                                    (        1        )            where V is the sheath voltage, A is the electrode surface area, n is between 1.3 and 3 in the present set-up, and the indices “1” and “2” refer to the driven and the processed electrode, respectively.
The driven electrode surface expansion concept has never been applied to an asymmetric discharge with a cylindrical coaxial geometry. A need, therefore, exists for a system and a method to apply the driven electrode surface expansion concept to an asymmetric discharge with a cylindrical geometry.
Additionally, it is known that in wet etching processes the etching rate increases with the temperature. However, increasing the etching rate by increasing the temperature has never been attempted in dry plasma processes. A need, therefore, exists for a system and a method for increasing the etching rate by increasing the temperature of a dry plasma process.